25th May 2025

In a retrospective case-control study looking at the relationship between arsenic exposure and bladder cancer, data revealed that 100 of the cases and 50 of the controls were exposed to arsenic in drinking water.

In a retrospective case-control study looking at the relationship between arsenic exposure and bladder cancer, data revealed that 100 of the cases and 50 of the controls were exposed to arsenic in drinking water. 500 cases and 1,000 controls were examined during the ten years of the study. 

What is the odds ratio of developing bladder cancer in those exposed to arsenic?

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